Improvement in flexible blackboards



I. R. MINEHART.

FLEXIBLE BLACKBOARD.

No.184,541. Patented Nov.21, 1876.

UNITED STATES PATENT QFFIGE.

JOHN R. MINEHART, OF BROWNSVILLE, PENNSYLVANIA, ASSIGNOR TO I HARRY W. MINEHART, OF SAME PLACE.

IMPROVEMENT IN FLEXIBLE BLACKBOARDS.-

Specification forming part of Letters Patent No- 184,541, dated November 21, 1 876 application filed April 4, 1876.

To all whom it may concern Be it known that 1, JOHN R. MINEHAR'I, of Brownsville, Fayette county, Pennsylvania, have invented anew and Improved Blackboard, of which the following is a specification:

Figure 1 represents a front View, and Fig. 2 a vertical transverse section, of my improved blackboard, on line :20 as, Fig. 1; and Figs. 3 and 4 are a front and rear view of the rubbing-piece.

Similar letters of reference indicate corresponding parts.

The invention relates to an improved blackboard for schools and family purposes, that has the advantage of being readily rolled up into compact shape like a map, to be shipped and stored with greater convenience; and the invention consists of a blackboard made of suitable fabric with a slate surface, and

mounted on top and bottom rollers, being tightly stretched for use by elastic straps of the lower strip or roller applied to suitable nails. Y In the drawing, A represents a sheet of any suitable fabric and size, according to the purposes required. The sheet A is provided with a slate surface of sufficient thickness and elasticity as not to break in handling or rolling up, and not rub off easily by use.

The slate-covered sheet A is attached to top and bottom rollers or strips B, by which the slate sheet is hung up and stretched. The top roller is hung, by two or more rings, a, to hooks or nails, and the lower strip or roller, by means of elastic straps b, with rings d, to fastening-points at such distance below the bottom strip that when the rubber straps are attached, the blackboard is tightly stretched on the wall.

The chalkmarks are wiped out by means of a moistened sponge or a soft-rubber block, 0. (Shown in Figs. 3 and 4.)

The blackboard is conveniently rolled up and stored after use, and may be readily and cheaply shipped in the manner of maps to any address.

Having thus described myinvention,Iclaim as new and desire 'to secure by Letters Patent The combination of the elastic straps I), having end rings, with the bottom roller or strip of the flexible blackboard A, as and for the purpose set forth.

J B. MINEHART.

Witnesses: A. G. 3009211, B. D. MASON. 

